SOLUTION: The graph and table below show the income for a local company. Use this information to predict the income in the year 2005. Year Total Income (in millions) 1980 $6.3 1985 $21.

Algebra ->  Equations -> SOLUTION: The graph and table below show the income for a local company. Use this information to predict the income in the year 2005. Year Total Income (in millions) 1980 $6.3 1985 $21.      Log On


   

Question 114916: The graph and table below show the income for a local company. Use this information to predict the income in the year 2005.
Year Total Income (in millions)
1980 $6.3
1985 $21.5
1990 $39.8
1995 $57.4
2000 $65.3
Can someone please help me with this one, I am baffled. I add them all together right? Then what?

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
he graph and table below show the income for a local company. Use this information to predict the income in the year 2005.
Year Total Income (in millions)
1980 $6.3
1985 $21.5
1990 $39.8
1995 $57.4
2000 $65.3
Can someone please help me with this one, I am baffled. I add them all together right? Then what?
:
I think they want you find the slope using the given data.
Let 1980 represent x = 0
then x = 5 for 1985
and x = 10 for 1990
etc
x = 20 for the year 2000
:
let income be represented by y
:
Find the slope using the slope formula: m = %28y2-y1%29%2F%28x2-x1%29
:
Using the given data: x1 = 0; y1 = 6.3 and x2 = 20; y2 = 65.3
m = %2865.3-6.3%29%2F%2820+-+0%29 = 59%2F20 = +2.95 is the slope
:
Find the equation using the point/slope equation; y - y1 = m(x - x1)
:
y - 6.3 = 2.95(x - 0)
y = 2.95x + 6.3
:
Plot this equation, it should look like this:
+graph%28+300%2C+200%2C+-10%2C+30%2C+-20%2C+100%2C+2.95x+%2B+6.3%29+
:
You can see that in 2005 (x=25) the income will be about 80 million
:
You can find the exact prediction. Substitute 25 for x in our equation
y = 2.95(25) + 6.3
y = 73.75 + 6.3
y = 80.05 million in 2005
:
Did this help?